The coal gasification process includes heating to pyrolyze a raw material such as coal and recovering product gas as an energy source for power generation or the like. In this coal gasification process, coal serving as the raw material is fed into a gasification furnace, and oxygen containing gas and high-temperature steam, which serve as oxidants, are supplied into the gasification furnace to partially combust the raw material in the gasification furnace, so that generated heat is used to pyrolyze and gasify the remaining uncombusted raw material (see Patent Document 1, for example).
Currently, the coal gasification process described above is mainly used for coal gasification hybrid power generation, which can advantageously utilize coal resources that are widely spread all over the world as well as are reserved adequately. Moreover, the coal gasification hybrid power generation realizes an excellent power generation efficiency, so that suppressed are the amounts of resultant substances such as carbon dioxide, sulfur oxides, and nitrogen oxides per amount of generated power.
Meanwhile, in the coal-based direct ironmaking process, blended raw materials including an iron oxide containing substance and coal serving as a reductant are preliminarily formed into agglomerates such as pellets or briquettes, and the agglomerates are supplied into a rotary hearth furnace. While moving in the rotary hearth furnace, the blended raw materials are heated with heat generated by a heating burner or with product fuel gas, so that the iron oxide in the blended raw materials are reduced by the reductant to obtain metallized iron (reduced iron) (see Patent Document 2, for example).